CVE-2026-63343 (GCVE-0-2026-63343)

Vulnerability from cvelistv5 – Published: 2026-08-21 14:53 – Updated: 2026-08-21 21:44
VLAI
Title
Arbitrary File Read/Write: metadata.yaml symlink in image allows host filesystem access as root
Summary
Incus is a system container and virtual machine manager. Prior to version 7.3.0, a malicious image containing a `metadata.yaml` symlink pointing to an arbitrary host path allows an authenticated Incus user to read or overwrite any file on the host as root via the instance metadata API. The `exec-output` and `templates/` paths were patched in a prior release using `Lstat` rejection and `os.OpenRoot` confinement; `metadata.yaml` was not included in either patch and remains exploitable. Version 7.3.0 patches the issue.
Severity
9.9 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-21 21:00 UTC
CWE
  • CWE-73 - External Control of File Name or Path
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7737 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
lxc incus Affected: < 7.3.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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